Load data for .257 Roberts + .257 | 70gr | Sierra Blitzking

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Load Specifications

(Use the Personalized Load Calculator below to adjust )

Bullet:	.257 \| 70gr \| Sierra Blitzking
Manufacturer SKU:	1605
Bullet Weight:	70gr \| 4.5g
Bullet Diameter:	0.257" \| 6.53mm
Bullet Length:	<<locked>>
Caliber:	.257 Roberts load data
Case Length (l3):	2.233" \| 56.7mm
Cartridge Length (C.O.L.):	<<locked>>
Seated Depth:	<<locked>>
Shank Seated Depth:	<<locked>>
Case Capacity:	56.0 Grains of Water \| 3.64 cm³
Primer Size:	Large Rifle (LR)
Max. allowed Pressure:	51488 psi \| 3550 bar
LID:	LID_B5786_C241
Last updated:	2026-01-22

Load data for 130 loads in caliber .257 Roberts with .257 | 70gr | Sierra Blitzking bullet and 65 powder(s). The key underlying parameters are shown in the table above.

Important Notice: DO NOT go below Minimum Charge or above Maximum Charge unless there are reasons. Since xxlreloading.com has no control over the equipment and components used by the customer and the data used in connection with the website, any responsibility and liability for the results achieved is rejected. Also see our Terms of Service.

Questions regarding the load data: Please read the information in the next tab "Explanations".
A load must fulfill certain criteria to be listed in the default view below - see "powder criteria to fulfill to be listed".

Our load data might deviate from other sources - see the "most common reasons for deviations".

All loads are based on the bullet and case dimensions shown under "Load Specifications" - see "reloading suggestions" if you deviate.

You can set your specifications in the "Personalized Load Calculator".

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Our default view only displays powders/loads that fulfill certain criteria: Max pressure of a load <=90% of Max. Standardized Pressure. Fill Rate (Min FR): >80% and <100% for rife loads, >60% and <100% for pistol loads. Min. Propellant Combustion (Min z): >90% for rifle loads , >80% for pistol/revolver loads. Relax these criteria at your own risk to potentially get more powders shown in the load tables.
Case Length (Inch)
Case Length (mm)
CaseCapacity (GoW)
Min z (%)
Min FR (%)
Max FR*
Barrel Length (Inch)
Barrel Length (cm)
Safety Buffer (%)
.

Click on the desired row in the tables below to add a specific load / powder to your Diary and manage there.

Powder	Charge	FR	MaxP	%	V(0)	z
ADI AR 2206H	<<locked>>	89%	45745	89%	**69	95%
[ADI AR 2208]*	<<locked>>	94%	45687	89%	**27	94%
Accurate 2015	<<locked>>	85%	46267	90%	**37	100%
[Accurate 2200]*	<<locked>>	87%	45919	89%	**17	93%
Accurate 2460	<<locked>>	83%	46238	90%	**46	97%
Accurate 2495 👍	<<locked>>	89%	45716	89%	**99	100%
Accurate 2520	<<locked>>	88%	45948	89%	**79	98%
Accurate 4064 👍	<<locked>>	94%	45716	89%	**89	99%
Alliant AR-Comp	<<locked>>	88%	46180	90%	**02	100%
[Alliant Power Pro 2000-MR]*	<<locked>>	91%	46006	89%	**48	93%
Alliant Reloder- TS 15.5	<<locked>>	95%	45730	89%	**86	96%
[Alliant Reloder-15]*	<<locked>>	92%	45440	88%	**76	94%
[Alliant Reloder-17]*	<<locked>>	96%	42931	83%	**79	94%
[Baschieri & Pellagri 107]*	<<locked>>	89%	45469	88%	**66	93%
Bofors RP3	<<locked>>	95%	45339	88%	**79	96%
Hodgdon BL-C2	<<locked>>	88%	45905	89%	**99	96%
Hodgdon Benchmark	<<locked>>	85%	45455	88%	**87	97%
[Hodgdon CFE223]*	<<locked>>	93%	45295	88%	**83	93%
Hodgdon H322 👍	<<locked>>	85%	45223	88%	**66	99%
[Hodgdon H380]*	<<locked>>	94%	45847	89%	**60	92%
[Hodgdon VARGET]*	<<locked>>	94%	46035	89%	**46	94%
Hodgdon TrailBoss	<<locked>>	96%	32155	62%	**95	100%
IMR 3031 👍	<<locked>>	93%	46238	90%	**38	100%
[IMR 4064]*	<<locked>>	95%	45977	89%	**40	94%
IMR 4895	<<locked>>	91%	45397	88%	**89	95%
IMR 8208 XBR	<<locked>>	87%	45527	88%	**33	96%
Lovex D073.5	<<locked>>	83%	45818	89%	**37	97%
Lovex D073.6	<<locked>>	90%	45948	89%	**79	98%
Lovex S060	<<locked>>	88%	45542	88%	**81	95%
Lovex S062	<<locked>>	93%	46325	90%	**60	97%
Norma 201	<<locked>>	90%	46282	90%	**56	97%
Norma 202 👍	<<locked>>	90%	45948	89%	**69	99%
Norma 203B	<<locked>>	93%	45542	88%	**83	95%
[Ramshot Big Game]*	<<locked>>	93%	45469	88%	**79	94%
[Ramshot TAC]*	<<locked>>	87%	45614	89%	**04	91%
Ramshot Wild Boar	<<locked>>	88%	46166	90%	**73	95%
Ramshot X-Terminator	<<locked>>	84%	45672	89%	**04	95%
ReloadSwiss RS 14	<<locked>>	96%	32256	63%	**44	100%
ReloadSwiss RS 40	<<locked>>	84%	46035	89%	**53	98%
[ReloadSwiss RS 52]*	<<locked>>	91%	45890	89%	**65	94%
ReloadSwiss RS 60	<<locked>>	96%	45992	89%	**74	98%
Rottweil R 901	<<locked>>	87%	45411	88%	**23	98%
Rottweil R 902	<<locked>>	91%	45556	88%	**27	96%
Rottweil R 903	<<locked>>	96%	44614	87%	**56	95%
SNPE Vectan SP 11	<<locked>>	95%	45513	88%	**99	95%
[SNPE Vectan SP 7]*	<<locked>>	88%	45847	89%	**20	92%
SNPE Vectan SP 9	<<locked>>	90%	45890	89%	**50	95%
SNPE Vectan Tubal 3000	<<locked>>	88%	45745	89%	**74	99%
SNPE Vectan Tubal 5000	<<locked>>	94%	45498	88%	**71	99%
Shooters World Match Rifle	<<locked>>	90%	45948	89%	**79	98%
Shooters World Precision	<<locked>>	93%	46325	90%	**60	97%
Somchem S321	<<locked>>	85%	45832	89%	**56	97%
Somchem S335	<<locked>>	88%	45527	88%	**87	99%
Somchem S341	<<locked>>	88%	45585	89%	**27	95%
Somchem S355	<<locked>>	96%	45905	89%	**66	95%
Vihtavuori N130	<<locked>>	84%	45498	88%	**74	100%
Vihtavuori N133	<<locked>>	91%	46151	90%	**91	100%
Vihtavuori N135	<<locked>>	97%	43976	85%	**23	100%
Vihtavuori N140	<<locked>>	92%	45745	89%	**37	99%
Vihtavuori N150	<<locked>>	97%	39102	76%	**82	95%
Vihtavuori N530	<<locked>>	86%	46296	90%	**76	97%
Vihtavuori N540	<<locked>>	91%	45368	88%	**50	99%
[Winchester 6.5 StaBALL]*	<<locked>>	97%	41191	80%	**89	94%
Winchester 748	<<locked>>	85%	45498	88%	**99	97%
Winchester StaBALL Match	<<locked>>	83%	45571	89%	**73	96%

Max Load - Barrel Length: 23.60''

Powder	Charge	FR	MaxP	%	V(0)	z
[ADI AR 2206H]*	<<locked>>	81%	35462	69%	**00	91%
[ADI AR 2208]*	<<locked>>	86%	36100	70%	**94	90%
Accurate 2015	<<locked>>	81%	40408	78%	**99	100%
[Accurate 2200]*	<<locked>>	82%	39508	77%	**53	90%
Accurate 2460	<<locked>>	81%	42322	82%	**61	97%
Accurate 2495	<<locked>>	81%	34809	68%	**40	98%
Accurate 2520	<<locked>>	81%	35781	69%	**36	95%
[Accurate 4064]*	<<locked>>	81%	29269	57%	**46	94%
Alliant AR-Comp	<<locked>>	81%	35621	69%	**69	100%
[Alliant Power Pro 2000-MR]*	<<locked>>	88%	40422	79%	**97	90%
[Alliant Reloder- TS 15.5]*	<<locked>>	84%	31589	61%	**12	90%
[Alliant Reloder-15]*	<<locked>>	85%	35824	70%	**23	90%
[Alliant Reloder-17]*	<<locked>>	91%	36230	70%	**79	90%
[Baschieri & Pellagri 107]*	<<locked>>	83%	37681	73%	**66	90%
[Bofors RP3]*	<<locked>>	84%	31386	61%	**09	90%
[Hodgdon BL-C2]*	<<locked>>	81%	36100	70%	**56	93%
Hodgdon Benchmark	<<locked>>	81%	39972	78%	**63	95%
[Hodgdon CFE223]*	<<locked>>	88%	39189	76%	**28	90%
Hodgdon H322	<<locked>>	81%	39436	77%	**22	98%
[Hodgdon H380]*	<<locked>>	90%	40190	78%	**22	90%
[Hodgdon VARGET]*	<<locked>>	87%	36405	71%	**00	90%
Hodgdon TrailBoss	<<locked>>	81%	25280	49%	**14	100%
IMR 3031	<<locked>>	81%	31067	60%	**51	96%
[IMR 4064]*	<<locked>>	87%	35317	69%	**71	90%
[IMR 4895]*	<<locked>>	83%	34345	67%	**07	90%
[IMR 8208 XBR]*	<<locked>>	81%	37463	73%	**33	94%
Lovex D073.5	<<locked>>	81%	41901	81%	**51	96%
[Lovex D073.6]*	<<locked>>	81%	33562	65%	**68	94%
[Lovex S060]*	<<locked>>	81%	36883	72%	**71	92%
[Lovex S062]*	<<locked>>	81%	31270	61%	**66	91%
[Norma 201]*	<<locked>>	81%	34824	68%	**61	93%
Norma 202	<<locked>>	81%	34693	67%	**94	96%
[Norma 203B]*	<<locked>>	84%	34389	67%	**91	90%
[Ramshot Big Game]*	<<locked>>	86%	36071	70%	**46	91%
[Ramshot TAC]*	<<locked>>	84%	42235	82%	**28	90%
[Ramshot Wild Boar]*	<<locked>>	81%	36419	71%	**27	91%
[Ramshot X-Terminator]*	<<locked>>	81%	41089	80%	**89	93%
ReloadSwiss RS 14	<<locked>>	81%	25498	50%	**64	100%
ReloadSwiss RS 40	<<locked>>	81%	42366	82%	**68	97%
[ReloadSwiss RS 52]*	<<locked>>	85%	36825	72%	**25	90%
[ReloadSwiss RS 60]*	<<locked>>	85%	31459	61%	**35	90%
Rottweil R 901	<<locked>>	81%	38363	75%	**59	97%
[Rottweil R 902]*	<<locked>>	81%	32924	64%	**99	92%
[Rottweil R 903]*	<<locked>>	87%	32430	63%	**41	90%
[SNPE Vectan SP 11]*	<<locked>>	88%	35360	69%	**30	90%
[SNPE Vectan SP 7]*	<<locked>>	85%	40234	78%	**86	90%
[SNPE Vectan SP 9]*	<<locked>>	81%	34229	66%	**51	90%
SNPE Vectan Tubal 3000	<<locked>>	81%	36724	71%	**61	96%
SNPE Vectan Tubal 5000	<<locked>>	81%	29849	58%	**71	95%
[Shooters World Match Rifle]*	<<locked>>	81%	33562	65%	**68	94%
[Shooters World Precision]*	<<locked>>	81%	31270	61%	**66	91%
Somchem S321	<<locked>>	81%	40379	78%	**32	95%
Somchem S335	<<locked>>	81%	36129	70%	**64	97%
[Somchem S341]*	<<locked>>	81%	35114	68%	**74	91%
[Somchem S355]*	<<locked>>	86%	32358	63%	**22	90%
Vihtavuori N130	<<locked>>	81%	40741	79%	**69	100%
Vihtavuori N133	<<locked>>	81%	34098	66%	**09	98%
[Vihtavuori N135]*	<<locked>>	81%	26426	51%	**35	94%
Vihtavuori N140	<<locked>>	81%	32140	62%	**95	95%
[Vihtavuori N150]*	<<locked>>	88%	29254	57%	**04	90%
Vihtavuori N530	<<locked>>	81%	39711	77%	**09	95%
[Vihtavuori N540]*	<<locked>>	81%	32169	62%	**12	94%
[Winchester 6.5 StaBALL]*	<<locked>>	91%	34156	66%	**05	90%
Winchester 748	<<locked>>	81%	38957	76%	**38	95%
[Winchester StaBALL Match]*	<<locked>>	81%	41814	81%	**87	94%

Start Load - Barrel Length: 23.60''

Any powder missing? Then click here.

FR ... fill rate of the cartridge in percent

MaxP ... max. pressure of load in psi or bar

% ... max. pressure of load in percent of the maximum allowed pressure for this caliber

V(0) ... muzzle velocity in feet per second (fps) or meters per second (m/s)

z ... powder burnt in percent

[...] *... not dangerous but load has suboptimal powder burnt with possible characteristics such as extensive muzzle flash or inaccurate loads.

[...] ²... fill rate low - you might want to consider using a filler to ensure proper ignition.

[...] ᴾ... possible press load - work up slowly to this load while watching for signs of excessive pressure.

👍 ... recommended powder/load for this caliber and bullet combination based on its ballistic performance.

<<locked>>... you need to buy an access license to unlock the data